Graph visualizers, such as Graphviz, can take a formal representation of the nodes and edges of a graph and produce an image from them. What’s a program or programming library that can do the reverse; that is, recognize an image of a graph and produce a formal representation? I would be interested in software for recognizing a bitmap as well as the easier case of recognizing a graph from an SVG that follows a standard structure. Either way, restrictions on the graph’s appearance are okay. Also, I require only the extraction of node-and-edge relationships, not other things like text labels of nodes.
